Dealing with self-signed SSL certificates - php

I deal a lot with self-signed SSL certificates as I deploy the systems in offline environments. The problem is that for example Chrome users has to deal with "dangerous site errors" etc, also if I want to even use GuzzleHttp library for connecting to any other service I have to setting secure to none. What's the best way to deal with it?

If you have a Selfsigned certificate this can be made trusted to the specific system that you use. If others from your office uses it then they may need to add this Selfsigned certificate as trusted by adding it to their system certificate store to make this trusted.
When it comes to office environment it is better to contact the Administrator and add the certificate to all the systems (certlm.msc in run for local machine / certmgr.msc for current user) so your colleagues won't get this dangerous site errors.

Related

CA Public Certificate Bundle for cURL

I have a SSL enabled eCommerce website which uses cURL for payment processing. Everything is running well but recently I learned about "CA Public Certification Bundle for cUrl" that its a good idea to use it for cURL connections.
If this is true than can someone tell me how or how is it better/different than using the standard SSL?
Doesn't the SSL already provide some kind of certification for all connections?
Any HTTPS client connected to an HTTPS server will get its certificate (in fact, it can be a certificate chain). This server certificate must then verified by the client to authenticate the server.
This is normally done by using a number of CA certificates that are configured on the client as trust anchors (i.e. this is what you trust in advance, before encountering the server certificate). The client tries build a chain between the last element of the server chain and one of the CA certificates in its trust anchors. If there is such a valid chain the server certificate is trusted.
A "CA certificate bundle" would be a set of trust anchors. You can build your own by looking for CAs you're willing to trust, or you can use an existing bundle. Most OSes or browser come with an existing bundle. cURL in itself doesn't but it can rely on a pre-defined location (set at compile time) or it also suggests to use the Firefox bundle (via a conversion mechanism). (You can override default setting via extra options, on the command line or via the API.)
Certificate Pinning (which you also mention) has nothing to do with a CA cert bundle. In fact, it's almost the opposite. Instead of relying on 3rd party trust anchors (the certification authorities), you explicitly "pin" a set of server certificates you know as directly trusted. They're not used to verify other certificates, instead, you compare the certificate you get with the exact certificate you're expecting for that host (or at least you compare public keys). This is more like having a reference mapping from server name to certificate (or to public key) and comparing what you get from that host with the reference you have. Of course, this can only work for a reasonably small set of certificates in practice, unlike the CA (PKI) approach which is designed to let you authenticate parties you have never encountered before (via a 3rd party: the CA).
How is it better/different than using the standard SSL?
Doesn't the SSL already provide some kind of certification for all connections?
Using a CA certificate bundle isn't different than using "standard SSL", it is what's commonly used for SSL/TLS connections. You often don't see it because that CA bundle is often supplied with your client (or with the OS).
Note that strictly speaking, this is orthogonal to SSL/TLS itself, which mainly just says you should authenticate the server. Certificate verification (the PKI way, via CA certificates) is defined in a different specification, also complemented by a specification on how to verify the name in the certificate (and the HTTPS specification of course).
Found a great answer here. The comment above really helped. The exact keyword I was looking for was "Certificate Pinning".

SSL during php site development

I'm about to develop a new website and will require a EV SSL certificate when the site is pushed to the production server. My question is during development I won't have an EV SSL certificate (although I could have a self signed cert if needed). If I develop my PHP site without an SSL cert then push it to my production server, is it likely to work or are there going to be a ton of issue surrounding this?
Also if I do develop locally with a self-signed SSL cert then push to the production server where it will have the EV SSL, is that like to cause any issues?
I just thought I'd clarify these few point before diving in and getting carried away. Are there any industry standards or best practices on how one should develop a site locally that will end up with a SSL certificate?
Note: I'm going to be using the Laravel framework if that makes any difference to answering this question.
If you are using Laravel 3, you can find a key in application/config/application.php for 'ssl'. If you set this to false (preferably in your dev or equivalent config), then when you generate a URL to a secure route with any of the URL helper methods (URL::to_secure, etc.), Laravel will automatically convert those links to http in that environment.
I do not know of a config option for this in L4, but what you could do is define your own config variable for it and use that in your helpers URL::to('foo', null, null, Config::get('app.ssl',true)). This way, you can set 'ssl' to false in your config to use it just like L3.
EDIT: I just caught Taylor in IRC and his explanation for the omission of the SSL config in L4 is because he recommends actually setting up SSL on your development environment as you had suggested. For development purposes, a self-signed cert should be fine.
Normally you shouldn't have any problems, switching from an HTTP to an HTTPS server. Using a self signed certificate for development is surely a good idea though.
There are two major points that can go wrong:
Your application builds absolute links starting with 'http://'. This problem you can prevent using a self signed certificate, or with building only relative URL's.
The security settings of the session require SSL (e.g. the cookie should be restricted to SSL only). This would more be a problem on the development environment and again this problem can be prevented with a self signed certificate.

Authenticate Web Browser with SSL certificate

Is it possible to authenticate a web browser using an ssl certificate.
Say i store a private key in my application, is there any way to read a key from a browser and try to authenticate based on that?
You can authenticate a browser/user using SSL/TLS client-certificate authentication.
The client certificate must be requested by the server, so you'd need access to the server configuration (not just installing some PHP code on a shared server). This is done at the SSL/TLS layer (in fact, the mechanism is not specific to HTTPS): the server requests the client-certificate during the SSL/TLS handshake (sometimes via a renegotiated handshake). In Apache Httpd, this is typically done via SSLVerifyClient (although you'll need to specify other options too).
The server will then verify the certificate against the CAs you've configured it with (possibly your own, and possibly independent of the CAs used for the server certificate itself). (Alternatively, you could disable certificate verification at the server level in some cases, and have the PHP application do it, but this is a bit more advanced and you'd need to know what you're doing.)
You can access the client certificate from your application and obtains its Subject DN (or alternative names), to identify the client.
It's not clear whether you're after identifying a browser or a user. In the end, everything goes through the browser anyway, but client certificates tend to be allocated to users. Users would have to install that certificate into their browser.
EDIT: For further details, it would help if you could clarify your question and what you intend to do with this.
Is it possible to authenticate a web browser using an ssl certificate.
Say i store a private key in my application, is there any way to read
a key from a browser and try to authenticate based on that?
Firstly, strictly speaking, there's no such thing as an "SSL certificate", since multiple types of certificates can be used for SSL/TLS, and some of these same certificates can also be used for other purposes than SSL/TLS. Typically, "SSL certificate" means "X.509 certificate in the context of SSL/TLS".
Therefore, authenticating a web browser using an SSL certificate implies doing it at the SSL/TLS layer. (There have been attempts to implement message-level security using X.509 certificates at the HTTP layer, but they're not widely supported by browsers.)
Secondly, the private key is held by the remote party that you authenticate. The local party that authenticates the remote party doesn't see any private key. If you (as a server) want to authenticate a web browser, it's the browser that needs to have the private key, not your (presumably PHP) application. In this context, it's not quite clear why your (PHP?) application would have/need a private key if it's the browser that you want to authenticate.
What your verifying application may need (if it's not done by the server itself) is a CA certificate to be able to verify the client certificate it is presented with (or at least some form of trust anchors with which to verify the client certificate). There's no private key required here, just public keys and certificates, unless you want your application to be a CA too.
Indeed, you could have your application be a mini CA. It could make the browser generate a key-pair and send a certificate request to the server (there are mechanisms to have a web page make the browser do all that). Then the server would generate the certificate and make the browser import it back against its private key. Subsequently, the browser could use this certificate for authentication with that server (or other servers that would recognise these certificates).
No, you cannot do that.
There is some development going on, and a few day ago W3C has made a proposal for a encryption standard.
You can however put a key in a cookie and use that to identify. This is the default PHP session id behavior.

PHP WebDAV Server Certificate Failed

Currently setting up a backup solution that sends a database dump and some other files from a Wordpress network to a NAS on my LAN, via WebDAV. I have installed PHP WebDAV on my web server and the basic code to get that that to work is:
webdav_connect('http://webdav.example.com/dav', 'davuser', 'davpassword');
webdav_put('/your/nice/thing.txt', $data);
webdav_close();
The issue is, my NAS requires this connection to be done via HTTPS, so in a web browser you'd see a warning which you can ignore, but PHP gives the following warning and the code fails:
Warning: webdav_put() [function.webdav-put]: Server certificate verification failed: certificate issued for a different hostname, issuer is not trusted in /var/www/vhosts/blah/blah/blah.php on line 5
Is there a way in which I can ask PHP to ignore this, or will I need to obtain an SSL certificate? The domain name used for accessing the WebDAV service on my NAS is one provided by Dynamic DNS if that makes a difference.
Is there a way in which I can ask PHP to ignore this, or will I need to obtain an SSL certificate?
I don't know which HTTP Layer PHP WebDAV uses (which extension are you using?), but often it's possible to configure the underlying layer to ignore certificate errors.
If you need certificate verification for security reasons, you should obtain a valid certificate.
Just for completeness as I don't like leaving things un-answered. I've decided to access my WebDAV service via SMEStorage. They provide an API which developers can use for this sort of thing:
http://smestorage.com/?p=static&page=for_developers

Are there any good beginner tutorials for using SSL with your web app?

I have a program written in PHP, and I'd like to make sure that login pages etc. are all served over SSL. Is there any good start to finish tutorial for doing so?
Also, does this affect my code in any way, or is it just a matter of getting a SSL cert, and setting up a server correctly?
If your html code contains absolute urls ("http://my-domain.com/...") to:
stylesheets
images
javascripts
Browsers will complain "This page contains both secure and non-secure items".
Use relative urls if you can, or link to "https://my-domain.com/..." urls.
Use free certificates
You don't have to spend money to get valid SSL certificate:
Let’s Encrypt
Let’s Encrypt is a free, automated, and open Certificate Authority.
It depends on the hosting how easy this is to setup, it could be just a checkbox.
The process is well documented on https://letsencrypt.org/
StartSSL
For more traditional certificates, you can get a "StartSSL™ Free" from StartCom.
The site also contains information on installing the certificate.
Firstly a word of warning. if you are considering using SSL its because you have something to protect. Therefore take the time to understand what you are doing every step of the way. Security (not just SSL) is a minefield even for the experienced.
I don't know of any tutorials, but there are plenty of gotcha's you have to be aware of.
Rolling your own ssl cert for testing purposes is free, but you will need to install it on your server.
Most of the time your code does not need to be any different for an ssl page or non ssl as the code itself is ssl agnostic, but as Bob says you must be careful of things like images.
Also redirects can cause popups to warn the user of redirections.
To test if the code is being called from a browser using SSL check for the SSL flag $_SERVER['HTTPS'] this should be a non empty value if SSL is being used.
$ssl_is_on = $_SERVER['HTTPS'] ? true:false;
Personally I prefer to keep my SSL code in a separate folder altogether and use apache to direct all SSL connections to that folder. that way I can be confident a script that should be protected by SSL is not called from a non SSL connection.
If you are logging them in under SSL and then redirecting them to non SSL pages you may need to account for domains and cookies
for example I always use a different domain for ssl normally https;//secure.blah.com and then redirect them to the non secure domain http;//www.blah.com so your cookie domain will need to be blah.com the default is the full domain name which means cookies for secure.blah.com won't be sent to www.blah.com and therefore your users will never be logged in.
Don't use this technique if you use a shared domain name otherwise you could have a problem with cookie information being leaked.
DC
It should not affect your code. Add modrewrite rules to your Apache config. Yes, just obtain an SSL cert (you'll need to pay to have it signed by Verisign or another certificate authority).

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